Glass nanopore electrodes

The truncated conical-shaped glass nanopore electrode (for brevity, hereafter referred to as a glass nanopore electrode or GNE) comprises a Pt microdisk electrode sealed at the bottom of a conical-shaped pore in glass (1). The radius of the pore orifice can be varied between 5 nm and 1 pm. The GNE was developed as a structurally simple platform for nanopore-based sensors and for investigating molecular transport through orifices of nanoscale dimensions. 

Wang, G. Bohaty, A. K. Zharov, L White, H. S. Photon gated transport at the glass nanopore electrode. JAm Chem Soc 2006,128, 13553-13558. 

White, H. S. Bnnd, A. Mechanism of electrostatic gating at conical glass nanopore electrodes. Langmuir 2008, 24, 12062-12067. 

Wang, G. L. Zhang, B. Wayment, J. R. Harris, J. M. White, H. S. Electrostatic-gated transport in chemically modified glass nanopore electrodes. 7 Am Chem Soc 2006,128, 7679-7686. 

Zhang, B., Galusha, J., Shiozawa, P. G. et al. 2007. Bench-top method for fabricating glass-sealed nanodisk electrodes, glass nanopore electrodes, and glass nanopore membranes of controlled size. Anal. Chem. 79 4778-4787. 

The recessed nanopore electrode shown in Figure 2.2b comprises a Pt or Au microdisk electrode embedded at the bottom of a conical-shaped pore synthesized in a glass membrane. These electrodes are fabricated with pore orifice radii as small as a few nanometers. EDL gating refers to the ability to control the flux of redox-active molecules from the bulk solution to the electrode surface, through the orifice (Figure 2.25), by either chemical (e.g., pH) or external stimuli (e.g., photons) that... 

Figure 6. (A)AFM image of electrodeposited ZnO nanoparticles(B) UV-Vis spectra of Mb in pH 7 PBS (a) and on an ITO glass slide deposited with ZnO nanoparticles(b).CVs of ZnO (a), Mb (b), and Mb-ZnO (c)modified GE in PBS (pH 7.0) scan rate, 100 mV s 1 (Reprinted from Analytical Biochemistry, 350, G. Zhao, J. J. Xu, H. Y. Chen, Interfacing Myoglobine to graphite electrode with an electrodeposited nanoporous ZnO film, 147, Copyrights (2006) with permission fom Elsevier.

Instead of floating nanoelectrodes (CNTs), our laboratory [3-7] is able to fabricate 50 nm nanoslots on glass (inset in Fig. 3b) and is able to show concentration of ssDNA to the nanoslot. The same DNA concentration is shown with nanoporous membranes in Fig. 3, with a concentration factor of up to five orders of magnitude. Alternatively, 100 nm nanocolloids can be assembled into a nanocolloid crystal (a membrane) at a top-down electrode pair by nanocolloid DEP (Figs. Ic, 6). The 10 nm spacing between the nanocolloids focuses the electric field of the electrode gate and can rapidly (order of seconds) trap and concentrate ssDNA... 

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